Expressive writing is a theory-driven behavioral medicine intervention that is designed to enhance health and well-being through increased cognitive and emotional processing of traumatic events. Many studies have shown the health benefits of expressive writing in relatively healthy, non-clinical populations writing under highly controlled laboratory conditions. A few pilot studies have provided suggestive evidence of benefits of expressive writing on adjustment to cancer, but most of these studies have had less than ideal designs. The proposed study aims to: (1) Determine the feasibility of applying a brief, inexpensive expressive writing intervention to individuals recently treated for CRC; (2) Identify demographic and psychosocial factors that influence feasibility; (3) Determine the potential efficacy of expressive writing for improving a range of healthrelated quality of life outcomes (e.g., depressive symptoms, physical functioning and symptoms, social-emotional growth); and (4) Identify demographic and psychosocial factors that may influence the efficacy of the writing intervention. We will use a three-group, pre-post design, in which 183 women and men recently treated for Stage l-lll colon or rectal cancer will be randomly assigned to one of three conditions: expressive writing, control writing, or no writing. Data will be collected through structured, face-to-face interviews conducted shortly before the writing intervention and again at one and three months after the intervention. Primary outcomes include feasibility indicators (e.g., accrual and retention rates, acceptability of procedures, and adherence to writing instructions) and quality of life variables (general and cancer-specific, psychological depression, and social-emotional growth). Moderator variables include psychosocial variables (e.g., social constraints, intrusive thoughts) as well as socio-demographic and medical factors. Moderator analyses will focus on exploring who benefits from expressive writing and why. For instance, we predict that expressive writing will be most beneficial for people with CRC who: (a) have inadequate social support, or who feel constrained in discussing their cancer with others, and (b) have intrusive thoughts about their cancer, because the safe emotional expression of writing should buffer them from the negative effects of such unbidden thoughts on quality of life outcomes. Feasibility and efficacy data will be used to inform the development of a future randomized controlled trial.